Wire connecter



9 w. R. SOMMER 1,874,825

' WIRE CONNECTER Filed April 5, 1929 gv w wmxxy I ATTORNEY.

Patented Aug. 30, 1932 UNITED STATES PATENT OFFICE WIL IAM R. sOMMERj' EHACKENSACK, NEW JERSEY, ASSIGN'OR T JIEEY W'IRE coN- NECTOR COMPANY, orHAOKENSACK, NEW JERSEY, A CORPORATION on NEW JERSEY WIRE CONNECTERApplication filed April 5,

This invention relates to wire connecters, of the type used especiallyin electrical 1nsulations, in which the ends of the wires are screwedinto the connector which for that I purpose has a passage threaded toform a cutter. The invention is an improvement on the device of Patent-No. 1,635,293 in that Whereas the latter device must be made with boresof different diameters to receive, re-

spectively, a gang of two, three or four wires,

3 the invention makes it possible for the same device to receive two,three or four wires, by which I mean obtain a perfectly efiectual grip,and of course the good electrical con- 1 tact of the wires with eachother, without severing or otherwise'disrupting any wire, even if one bea stranded wire.

According to this invention the improved wire connecting devicecomprises an insulatgo ing body having a socket or bore therein openingthrough one end in the form of an inwardly tapering receiving mouth, anda thread-cutting wire-holding die member embedded in the body and havinga bore whose an walls are provided with cutting threads, the '4 bore ofsaid member comprising two distinct portions of different diameters,each having said threads and the portion of larger diameter beinglocated between and in communicano tion with the said mouth of theinsulating body and the portion of small diameter, whereby said portionsare adapted to threadably receive and form screw-thread holds on wiregangs of different diameters.

The drawing shows in Figs. 1, 2 and 3 a side elevation (partly 7 brokenaway) and right and left end elevations, respectively, of the improveddevice before its bores are tapped to form thread: cutting surfaces;

Fig. 4 a longitudinal section thereof after tapping;

Fig. 5 the device encased in an insulating body, said device and bodyappearing in longitudinal section; and

Fig. 6 a right hand end elevation of what is shown in Fig. 5.

Describing in detail that form of the invention shown in the drawing byway of example, 1 is a body of insulation which encases 1929. Serial No.352,656.

and rigidly holds the thread-cutting member 2, which in the example is ametal sleeve.

The member 2 is bored through axially, for a part of its length so thatit has a main and preferably cylindrical bore 3 and for the remainderthereof so that it has a tapering bore 4 which affords the entrance forthe wires to the member and whose small-er end adjoins and communicateswith bore 3. The larger end of bore 4; may be and preferably iscounter-bored in a bevel or conically, as at 5 and this beveled surfaceforms a continuation of the conical passage 6 formed in the body 1 andleading to the larger end of the bore 4. The surfaces of both bores 3and 4 are screwed-threaded and form thread-cutting surfaces or dies ofthe same hand. Each thread or cutting element, is preferably V-shapedand formed with its volutes spaced at their bases (Figs. 4 and 5), sothat it is actually a cutting element, as in my Patent No. 1,736,379,and not a mere deforming ele ment. In accordance with the preferredpractice in forming the bore 4; that end thereof which adjoins the bore3 is of somewhat greater diameter than the diameter of bore 3 and theirsurfaces merge in a shoulder 7 which tapers toward the latter bore. Thecutting of the thread in each bore is effected so that the resultingthread reaches substantially to the other bore, so that this taperingshoulder 7 will remain in the finished device. As will appear, while itis preferable that the end of the bore 4 adjoining the bore 3 besomewhat larger in diameter than the latter, an important matter is thatthe two bores shall merge together in a taper converging toward the bore3.

The single device, so formed, is adapted to admit and effectually gripand connect two, three or four wires (or even one wire having its endrebent and thus the equivalent of two) assuming of course that the gageof each wire where three or four are introduced is the same as that ofeach of the two wires. The admission and holding of a gang of two wiresis effected by screwing them into the threaded bore 3. WVhen a gang ofthree or four wires are to be connected by the device they are screwedinto the threaded bore 4: and the screwing-in operation continued untilmore or less of the tip of such gang becomes screwed also into the bore3. In this operation they begin to be gripped by the thread of bore 4:as soon as their combined diameter reaches the corresponding diameter ofthe taper of bore at, and later they are additionally gripped at the tipof the gang bv the thread of bore 3, this latter being permitted by thetaper at 7 and accompanied by a deeper thread-cutting in the bore 3 ofthe (mere tips of the) wires than in the case where only tWo wires arescrewed into bore 3, as described. So far as the bore 3 alone isconcerned-these four wires are not of course held as firmly as two wiresalone in bore 3, driven in to greater extent, would be, but thesupplemental grip on the four wires by the thread in bore 4 makes thehold on the four wires substantially equal to that effected on the two,and in any event it is sufficient so that no wire can be pulled out.This grip is moreover invariably attainable by not exerting screwing-inforce so as to distort or disrupt any wire or unduly twist the same.

If the two portions of the bore which are formed with wire-cuttingthreads Were portions of a single cone then if the pitch of the cone issteep enough to admit wire-gangs of different diameters the tapping ofthreads therein will only affect the mere tips of the Wires, withconsequently inferior gripping thereof by the device; and if the pitchof such cone is reduced so that there will be a tapping of threads in awire-gang therein introduced for an extent well back of its free endthen such cone, in order to admit Wire-gangs of different diameters mustbe very long, i. e., several times longer than is permissible of thesedevices in practice. herefore, instead of said portions of the borebeing portions of a single cone, I as explained form the portion 4 oflarger diameter adjoining the portion 3 than the latter, involvingproduction of the shoulder 7, which as indicated is preferably beveled;each portion may then very closely approach the cylindrical so that whena wiregang, whatever its diameter, is entered into the device it may bescrewed in and thereupon and thereby gripped not simply at its tip butfor a distance more or less back of its tip, without moreover increasingthe length of the device beyond that practically permissible.

Having thus fully described my invention, what I claim is:

1. A wire connecting device comprising an insulating body having asocket opening through one end and in such end formed with an inwardlytapering mouth, and a metal thread cutting member embedded in the socketinward of the mouth and having a bore opening into the inner end of saidmonth said bore having portions of different diameters, each providedwith die threads for cutting wires screwed into the bores and theportion of the bore of larger diameter being interposed between saidtapering mouth and the portion of smaller diameter.

2. A wire connecting device comprising an insulating body having asocket opening through one end and in such end formed with an inwardlytaperin mouth, and a metal thread cutting mem er embedded in the socketinward of the mouth and having a bore opening into the inner end of saidmouth, said bore having portions of different diameters that are incommunication and form at their juncture an internal shoulder, each ofsaid portions having individual die threads for cutting wires screwedinto the bores and the portion of the bore of larger diameter beinginterposed between said tapering mouth and the portion of smallerdiameter.

In testimony whereof I affix my signature.

YVILLIAM R. SOMMER.

